Jet Pump Deep Well 1hp The ProJet SL convertible jet pumps offer a proven cast iron self-priming design available in 1/2 - 1 HP models The ProJet SL convertible jets utilize easier priming and better range of performance from a complete line of shallow well, 4" double pipe, 2" and 3" single pipe jet packages Close-grained cast iron construction Reinforced polypropylene diffuser with brass wear ring